Surgical gut fulfills the requirements for the perfect suture more often than any other material.
a. Manufacture of catgut: derived from the submucosal connective tissue of the first one-third (about 8 yards) of the small intestine of healthy government inspected sheep. The intestine of the sheep has certain characteristics that make it especially adaptable for surgical use. It is of uniformly fine-grained tissue structure and possesses great tensile strength and elasticity.
b. Tensile strength of catgut: this suture material is available in sizes of 6-0 to 0 and 1 to 4, with 6-0 being the smallest diameter and 4 being the largest. The tensile strength increases with the diameter of the suture.
c. Kinds of surgical gut (catgut): this varies from plain catgut, the raw gut that has been gauzed, polished, sterilized, and packaged, to chromic catgut that has undergone various intensities of tanning with one of the salts of chromic acid to delay tissue absorption time. Some examples of these variations and absorption times are as follows: (1) Type A: Plain, 10 days (2) Type B: Mild chromic, 20 days (3) Type C: Medium chromic, 30 days (4) Type D: Extra chromic, 40 days
Suture needles may be straight or curved and have either a tapered round point or a cutting edge point. They vary in length, curvature, and diameter for various types of suturing.
1. Sizing: suture needles are sized by diameter and come in many sizes, depending on use.
2. Taper point: these cause small amounts of tissue damage and are most often used in deep tissues.
3. Cutting edge point: this is the preferred needle for suturing the skin because of the toughness of the skin.
4. Atraumatic (atraloc, wedged): these needles may either have a cutting edge or taper point and have the suture fixed on the end of the needle by the manufacturer to cause the least tissue trauma.
1. Examine the casualty carefully to determine what materials are needed to properly close the wound.
a. Select and prepare sterile instruments, needles, and suture materials.
b. The patient should be securely positioned so that access to the wound and suture tray is optimal. It is usually not necessary to restrain patients for suturing.
c. Make sure a good light is available.
2. Aseptic wound preparation is to be strictly observed. Use mask, cap, and gloves. Thorough cleaning and proper draping is essential.
3. Select an anesthetic with care. Consider the patients tolerance to pain, time of injury, medications the patient is taking or has been given, and the possible distortion of the tissue when the anesthetic is infiltrated.
The most common local anesthetic used is Xylocaine, which comes in various strengths (0.5%, 1%, 2%) and with or without epinephrine. Injectable containing epinephrine are never to be used on the fingers, toes, ears, or nose because of the vasoconstricting effect of the epinephrine. Epinephrine is also contraindicated in patients with hypertension, diabetes, or heart disease. The three methods of administration are topical, local infiltration, and nerve block. Topical anesthetics are generally reserved for ophthalmic or plastic surgery and nerve blocks are generally accomplished by an anesthesiologist or anesthetist for the surgical patient. For a corpsman, topical anesthesia is limited to the instillation of eyedrops for mild corneal abrasions after all foreign bodies have been removed. DO NOT attempt to remove embedded foreign bodies. Nerve blocks are limited to digital blocks wherein the nerve trunks that enervate the fingers or toes are anesthetized. The most common method of anesthesia used by a corpsman is the infiltration of the anesthetizing agent around a wound or minor surgical site.
Obtaining a digital block is a fairly simple procedure, but it should not be attempted except under the supervision of a medical officer or after a great deal of practice. The first step is cleansing the injection site with an antiseptic solution. The anesthetizing agent is then infiltrated into the lateral and medial aspects at the base of the digit with a small bore needle (25 or 26-gauge), taking care not to inject into the veins or arteries.